No. We pronounce the 't' very clearly. Little: [lit-l] If spoken very fast it might sound like a 'd', but it technically should actually be pronounced with a 't'.

Yes, we're saying a /d/ sound instead of a true /t/ sound. It depends on where the 't' falls in the word and whether or not it is stressed. Here is a nice explanation of it. https://netfiles.uiuc.edu/k-lee7/www/kesl/fayin/t_d.pdf

Some people mispronounce English. Sometimes peoples voices sound funny. Other times people are speaking with an accent you are not familiar with. So if an American speaks a "liddle" funny it is only because they are taking the language for granted. But most Americans pronounce "little" correctly.

I'm from Colorado and I speak cowboy English, ya'll. You gotta know that cowboys are the laziest people in the world... never walk if you can ride, never stand if you can sit and never sit if you can lie down. We don't say water, we say wader, we don't say letter, we say leder, we don't say twenty, we say twenny, and we say "howdy" too. Yippee Kiowa!

Hi,sandy...yes"liddle bid"